Dental casting-machine.



J. E. BURNS.

DENTAL CASTING MACHINE.

' APPLICATION FILED SEPT-15,1915. 1 1 9 1 659 I Patented July 18, 1916.

4 SHEETS-SHEET I.

IIVVENTOR Jahn; J5. Burns.

W I I ATTORNEY J. E. BURNS.

DENTAL CASTING MACHINE.

APPLICATION FILED SEPT. 15.'1915.

Patented July 18, 1916.

4 SHEETS-SHEET 2.

ATTORNEY v J.-E. BURNS.

DENTAL CASTING MACHINE. APPLICATION FILED SEPT. 15, 1915.

1,191,659. Patented July 18, 1916.

4 SHEETS-SHEET 3.

/Nl/ENTOR v ,foihn/Z', Bel/ma J. E. BURNS.

DENTAL CASTING MACHINE.

APPLICATION HLEDSEPT- I5, 1915- 1 Patenteu July 18, 1916.

4 SHEETS-SHEET 4.

757m 15. Burn/s,

ATTORNEY JOHN, BURNS, F FLUsHInG,"'i-rEW YORK.

I DEJSl'TAL CASTING-MACHINE.

Specification of Letters Patent.

Application filed September 15,1915. Serial Ito/50,833.

'1 0 all whom it may concern:

Be it known that l, J OIIN E. Bonus, a citizen of the United States, and resident of Flushing, in the county of Queens and State of New York, have invented certain new and useful Improvements in Dental Casting-Machines, of. which the-following is a specifiing, and the invention consists of flasks of various shapes and sizes for the various casting molds and adapted to be closed at their upper ends by an aii"-tight cap on the lower end of a hollow screw, operated by a hand wheel nut, and acting as a means fOI' COH' ducting the air from a tank to the flask. These and other details and objects of the invention are more fully described in the following specification, set forth in the claims and illustrated in the accompanying drawings, wherein;

Figure 1, is a side elevation of the press with an air-tank and connections. Fig. 2, is a front view'ofthe press. Fig. 3, is a vertical sectional view through the hollow screw, the nut and a flask. Fig. 4, is an end view of a split flask for casting plates. Fig.-

5, is a side View of the same. Fig. 6, is a perspective view of the smaller section of the split flask. Fig. '7, is a. top investment clamp for the same. Fig. 8, is a bottom investment clamp. Fig. 9, is a complete bottom for the assembled flask. Fig. 10. is a modified form showingthe cap secured by foot pressure. Fig. 11. is a modified form of press for moving the flask toward the cap by means of a hand lever. Fig. 12, and Fig. 13, are sectional views, at right angles, of a ca p adapted to deliver the compressed air to an elongated casting. Fig. 14, is a side view of a thimblc'used to equalize the distribution of air. Fig. 15. shows the base. disk for a smaller flask. Fig.1(3, is'a plan view of the sliding stand for the larger flask. Fig. 17. is a. view of a modified form of .press showing two flasks being used at the same time. Fig. 18. is a view of the. double frame modification partly in section.

ln order to carryout the objects of this in vcntion,flasks of various sizes are provided.

For crown, inlay or bridge work cylindrical or tapering flasks 5, shown in Figs. 1, and 3 and differing only'in size, are employed. The base block 4 has depressions 3 in its up per side which answer for seats for the flasks and the block is pivoted on the bed plate 2 which also carries the upright overhangingframe 1. The upper end of the frame 1 is squared and carries two clamps '6 which enter the annular groove of a. nut 7 that is providedwith a hand wheel 7 and playing in the nut 7 is a hollow screw 8 hav ing at one end a cock 9 and at the other end an internally threaded head 10. By means of the flexible the tank 12', and by means of the coil 13 and gas burner 14, the air is heated so that the sudden chill of cold air may not damage the casting. \Vhen the parts are properly adjusted and ready for the operation of the device, the cock 9 admits the air to thcupper end of the flask.

Screwed into the head 10 is the nipple 15 of a cap or plunger 16, fitting over the upper end of the flask 5 and having a gasket 17 interposed to make an air tight jointand to diffuse the air at the upper end of the flask a perforated thimble 18 'is provided and has a flange 19 secured between the upper end of the nipple 15 and the head 5.

Beneath the flask 5, as shown in Fig. 3. is placed a sheet metal disk 20 to reinforce the investinentiapd prevent its being blown out pipe 11" born: pressed air 1s supplied to the screw 8 from.

an snares earner emot PatentedJuly'is. 1916.

by the air pressure. but a small amount of air is allowed to pass through perforations in the disk and out the vent 21 in the block 4. \Vhen a smaller flask is used and located in the lower endof the depression 3. the bottom of the'depression will'be suflicierit'to support the investment and a small amount of air can escape through the vent;

When the mold'is Prepared and the molten metal poured in, it is placed in position and the hand wheel 7 and its nut are turned andthe screwr8' carried downward The .base block 4- is pivoted to,

the gasket l'i f'orming 'an' airtight,

is generally desired and especially a split flask such as shown in Figs. 4, 5, 10 and 11, and when this flask is. to be -used the. block 4 is swung around on its pivot 22 and a slide 25 inserted between the pin 24 and the block and shown in Fig. 16 where it will be seen that the slide is formed with a depression 26 of rectangular shape and having the vents 27 to allow the escape of air from the flask. This slide plate also has a knob 28 for convenience of handling. The large flask 29 is aubox formed of two pieces with open ends and having on each side to unite the sections a dove tail joint, one member 29 being a socket while the member 30 is a tongue to enter the socket. One side of each section also has a fork 31 to straddle a threaded stud 32 and be clamped in place by the nut 33 so that-the sections are held together.

In Fig. Gene of the sections 34 of the flask is shown ready to receive one half of the mold preparatory to securing to it the other half 35 and in order to receive the plastic cement, end pieces 36 and 37 are placed at the bottom and the top respectively. The cement forming half of the mold is allowed to set and these end pieces are removed and the other half 35 is secured to the part shown in Fig. 6, the conmotions are made and the flask placed on end as shown in Fig. 5 and a bottom piece 38, also shown in Fig. 9 is placed on the lower end. The mold is now half done and half of the flask is empty so that the empty half is filled and also allowed to set. The pattern may then be removed and themold is ready to receive the cast. This flask is also provided with a rectangular plunger cap 39 secured to the screw by means of the head 10 and having the thimble 18 secured therein.

In Fig. 10 is shown a device dispensing with the screw and using a foot lever 40 to depress the cap 39 which has ears at its four corners and through which pass the rods 41 surrounded by springs 42 and secured to a yoke 43 beneath the table 44. A pitman 45 connects the yoke 43 with the foot lever and the air pipe 46 passes freely through the. end of the standard 47. I

Another modification is shown in Fig. 11 where the air pipe 48 is held in the standard 49 by means of the set screw 50 and the flask 51 and base plate are moved upward toward the cap 53 by means of the hand lever 54. The plate 52 has the guide rods passing through the table and a stem 56 is connected with the lever by means of the pitman 57. In case that the casting isclon- ,distribute the air gated and it is desirable to distribute the air pressure over some length of flask interior, as in plate molds, the plunger cap shown in Figs. 12 and 13 is used and has the narrow and long channel 58 to receive and pressure introduced through the pipe 59. y

In the modified form shown in Fig. 17 two flasks 60 and (31 may be operated simultaneously. It consists of a double frame having the above described pipes and caps to allow the casting of different articles at various pressures without resetting the plunger caps, as a plate may be cast in flask (30 and an inlay or bridge cast in flask (31. The former being the larger article and requiring the most pressure, is cast first and the cock (i2 opened, cock (33 being closed. On opening cock 63 the pressure in the tank is reduced and the plate mold is set. The molten metal is now placed in the flask 61, the cap screwed down andthe cock 64 opened. It is obvious that a reduced pressure is sufficient for smaller castings such as bridge, crown or inlay work.

\Vh'at I claim as new is:

1. In a dental casting machine, the combination with a flask open at opposite ends, of a compressed air tank and pipe, a hollow screw connected with and forming a part of the pipe, a cap adapted to fit the end of the'flask, a nut to advance the screw and cause the cap to fit the end of the flask, and diffusing means at theend of the pipe.

2. In a'dental casting machine, the combination with a vertically divided flask open at each end, of a compressed air tank and flexible pipe, an overhanging frame, a nut swiveled in the frame, a hollow screw forming a continuation of the flexible pipe and working in the nut, a cap carried at the lower end of the hollow screw, and a perforated thimble at the end of the screw and within the cap.

3. In a dental casting machine, the combination with a flask to contain a mold, of a laterally vented base piece for the flask, a plunger rap adapted to fit and seal the top of the flask. a tank foncompressed air, a pipe from the tank vertically disposed above the flask, a hollow screw connected with the pipe and carryingthe cap and communicating with its interior, a gasket within the cap, and a. nut operating the screw to bring the cap and flask together to supply the latter with the compressed air.

Signed at New York in the county of New York and State of New York, this 23 day of August A. D. 1915.

JOHN E. BURNS. 

